In orthopedic surgery it is common to secure a bone screw to a patient's bone. Bone fracture repair is surgery to fix a broken bone using plates, nails, screws, or pins. It is common in the treatment of fractures to attach a plate to the bone utilizing bone screws. The resulting construct prevents motion of the fractured bone so that the bone can heal. Alternatively, one or more screws may be inserted across the break to hold it place.
In the treatment of spinal disorders, pedicle screws are inserted into the patient's vertebrae to serve as anchor points that can then be connected with a rod. This construct prevents motion of the vertebral segments that are to be fused.
In the treatment of detached tendons, screw-like tissue anchors are inserted into the patient's bone to serve as an anchor for the reattachment of the tendon.
One complication with the use of bone screws is the loss of fixation or grip between the bone screw and the patient's bone. Another complication with the use of bone screws is the stripping of the hole in the bone when the bone screw is inserted. This results in the loss of purchase and holding strength of the bone screw.
The presence of osteoporotic bone can increase the likelihood of complications by reducing the purchase or grip of the bone screw to the patient's bone, resulting in a loss of holding strength and loosening of the bone screw or pullout of the bone screw.
Current solutions to secure bone screws have not adequately addressed screw failure and the underlying causes of screw failure.